By Topic

Improved Sensitivity of AlGaN/GaN Field Effect Transistor Biosensors by Optimized Surface Functionalization

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$33 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

6 Author(s)
Xuejin Wen ; Department of Electrical and Computer Engineering, The Ohio State University, Columbus, ; Michael L. Schuette ; Samit Kumar Gupta ; Theodore R. Nicholson
more authors

In this paper, we optimize the AlGaN surface oxidation methods for AlGaN/GaN heterostructure field effect transistor (HFET) biological sensors. Reactive ion etching oxygen plasma, inductively coupled oxygen plasma, and piranha solution are used to oxidize AlGaN surface. After oxidation, X-ray photoelectron spectroscopy and water contact angle measurements are used to check oxidation effectiveness. Labeled streptavidin (SA) molecules are bound to the oxidized surface through linker molecules for comparison of surface modification effectiveness. Schottky diodes are fabricated to investigate the impacts of oxidation processes on electrical properties, such as Schottky barrier heights, sheet carrier concentrations, and interface trap densities. The results show that the inductively coupled plasma oxidation process has a superior behavior compared to the reactive ion etching oxygen plasma and piranha solution oxidation processes. AlGaN/GaN HFET protein sensors fabricated using the inductively coupled plasma oxidation process have exhibited improved sensitivity. An SA solution with the concentration as low as 4.73 pM were successfully detected.

Published in:

IEEE Sensors Journal  (Volume:11 ,  Issue: 8 )